% !Mode:: "TeX:UTF-8"%確保文檔utf-8編碼
\documentclass[border=2pt]{standalone}

\usepackage{tikz}


\usepackage{pgfplots}
\usepackage{fontspec}
\usepackage{xeCJK}
\setCJKmainfont[ItalicFont=方正楷体简体]{思源宋体 CN}
\setCJKsansfont{思源黑体 CN}
\setCJKmonofont{方正楷体简体}


\usetikzlibrary{intersections,calc,positioning}

\begin{document}

\begin{tikzpicture}
\draw (0,0) to[out=-50 ,in=180] (2,-2) -- (5,-2);
\fill[gray!50,rotate=-50] (0,0) rectangle (0.5,0.4);
\node[below] at (2.5,-2) {水平毛巾表面};

\begin{scope}[xshift=5cm]
\draw (0,0) to[out=-50 ,in=180] (2,-2) -- (5,-2);
\fill[gray!50,rotate=-50] (0,0) rectangle (0.5,0.4);
\node[below] at (2.5,-2) {水平棉布表面};
\end{scope}

\begin{scope}[xshift=10cm]
\draw (0,0) to[out=-50 ,in=180] (2,-2) -- (5,-2);
\fill[gray!50,rotate=-50] (0,0) rectangle (0.5,0.4);
\node[below] at (2.5,-2) {水平木板表面};
\end{scope}


\end{tikzpicture}


\end{document}